Visual aiming devices



March 17, 1970 M. H. CHWERS VISUAL AIMING DEVICES 2 Sheets-Sheet 1 Filed Nov. 28, 1967 INVENTOR y HICHREL HERBERT CHM/5R5 WM M March 17, 1970 M. H. cHwERs 3,500,545

VISUAL AIMING' DEVICES Filed Nov. 28, 1967 2 Sheets-Sheet 2 .EZIO- INVENWR H 1000a HERBERT (II/ms U.S. C]. 33-47 11 Claims ABSTRACT OF THE DISCLOSURE A visual sighting device, particularly, for use on a weapon such as a rifle comprises a thin walled metal sleeve fitted within a wider walled cylindrical tube of translucent material which, in turn, is fitted into a metallic sleeve or mounting block. The mounting block is carried on a post which may be mounted on a support or pillar secured on the weapon. The translucent cylindrical tube is advantageously formed with a uniform wall thickness cylindrical portion at one end and an outwardly flaring conical portion of outwardly increasing thickness at the opposite end which is adapted to be oriented toward the target. The increased thickness of translucent cylindrical tube of this end permits a greater inclusion of light around the thin walled metallic sleeve which functions to provide a ring which may be centered on the target. A ring of luminous material is formed in the vicinity of the boundary between the translucent tube and the mounting block so that the translucent tube is illuminated during the darkened hours to highlight the ring which will surround the target. The sight may be used as a single unit forming a peep-type sight or two such sights may be arranged at spaced locations along the length of the gun barrel. In the latter case, the two sights form a series of concentric rings which facilitate the locating of the target within the innermost ring.

SUMMARY OF THE INVENTION This invention relates to visual sighting systems and has particular, but not exclusive, application to weapons, navigation instruments, surveying instruments, optical equipment, directional radio equipment, and other equipment requiring visual sighting either as a sole means of aiming the weapon or instrument or as a preliminary or auxiliary aiming means hereinafter referred to as the type described.

In the use of, for example, direct fire weapons such as rifles, machine guns, cannons, rocket launchers and the like, it is desirable to have a sighting system which will allow speed of aim with the greatest accuracy whilst being effective under a wide range of lighting conditions. In effect it is desirable to have a sighting system which is extremely accurate whilst providing the best chance of a hit under operational conditions under all variants of light and in the shortest time.

Conventional sighting systems which are a means of relating the line of sight to the axis of projection require focus of a type of foresight which is in turn aligned on a target point at a distance, alternatively, optical devices provide a graticule which is in the focal plane of the eye, but this still requires strict use of one sense of the eye, i.e., in its focal plane. Aperture sights have been used for specific problems, in particular target shooting, where the target produces a geometrical pattern and is artificially illuminated, but this solution is incompatible against targets set against terrain backgrounds, with various shadows, light and background problems when the true circle of the aperture is distorted or lost.

Patented Mar. 17, 1970 It is known to use electronic aids, such as infra-red, in sighting systems under poor illumination conditions but due to the bulk and specialization requirements of these aids, the advantages thereof under normal conditions are limited. Furthermore, such known types of night sights do not solve daylight problems of fog, haze, smoke, directional lighting, background reflection and the like.

It is a principal object of the present invention to provide a universal day/night sighting device and system which encompasses great accuracy and speed of sighting or aiming under a wide range of light conditions including conditions where although the fixing point or target is visible to the naked eye, conventional sights would not be viewable.

It is a further object to provide a sighting device and system which allows a large area of background surrounding the target or fixing point to be clearly visible so as to facilitate speed of aim, and observe fire effect and other targets.

It is still a further object to provide a sighting device and system wherein focus is made by the eye on the fixing point or target only, thus allowing the user to fully concentrate on the fixing point or target without having to focus on a particular sighting system as part of the aiming procedure.

According to the invention there is provided a visual sighting device of the type described comprising an apertured member of light-transmitting material.

The apertured member may be of annular configuration in tube or disc form and preferably the light-transmitting material is translucent. The member may be disposed between inner and outer sleeves of opaque material the inner sleeve defining the aperture.

Preferably too, the outer surface of the inner sleeve and the inner surface of the outer sleeve are light reflective and the inner surface of the inner sleeve is non-reflective.

Preferably further, luminous material is located in the device so as to be capable of illuminating the tube of light-transmitting material. The invention also encompasses sighting systems incorporating the devices of the invention.

Elements constructed in accordance with the invention find particular application as sights of rifles and other small arms for both sporting and military use.

BRIEF DESCRIPTION OF THE DRAWINGS In orderthat the invention and its manner of performance may be more fully described, reference will now be made to embodiments illustrated in the accompanying drawings in which:

FIGURE 1 is a perspective view of a weapon showing alternative locations of the sighting device;

FIGURE 2 is an exploded view of one form of sighting device for attachment to a weapon as illustrated in FIGURE 1;

FIGURE 3 is a view in elevation of the sighting device of FIGURE 2 attached to the standard foresight protector of a weapon of the type illustrated in FIGURE 1, as seen by the user;

FIGURE 4 is a sectional view in side elevation of the sighting device;

FIGURE 5 is a two-part view of another embodiment of the device illustrating adjustment means;

FIGURE 6 illustrates use of the sighting device in daylight conditions with a terrain background;

FIGURE 7 illustrates use of the sighting device in bad light or night conditions with a terrain background showing the halo effect provided by the light-transmitting material;

FIGURE 8 illustrates use of the sighting device under normal conditions;

FIGURE 9 illustrates use of the sighting device with a moving target showing the facility for aiming-off; and

FIGURE 10 illustrates an embodiment of the sighting system using two sighting devices.

GENERAL DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, the embodiment as illustrated in detail in FIGURES 2, 3 and 4 comprises an outer cylindrical sleeve 5 of metal, the exterior of which has a non-reflective or matt black surface. Mounted within the sleeve 5 is an open-ended cylindrical tube 6 of a translucent material, for example, a methacrylate resin such as perspex which is a press or push fit within the sleeve 5, and mounted within said tube so as to be a press or push fit therein is a thin-walled metal sleeve 7. The tube 6 is formed for part of its length of frustoconical form as at S. The larger diameter end of the frusto-conical part of tube 6 is, in use, directed towards the fixing pont or target and acts to provide a greater light collection effect in said tube 6.

The inner surface of sleeve 7 is non-reflective, for example, matt black, and the outer surface of sleeve 7 and the inner surface of sleeve 5 are both polished so as to be highly reflective.

Part way along the outer surface of tube 6 there is provided a circumferential groove 9 containing a radioactivated luminous paint such as a promethium activated phosphorus paint. It will be appreciated that groove 9, may, if desired, be formed on the inner surface 10 of sleeve 5, or the inner surface 11 of tube 6. Instead of the luminous paint a hollow torus of translucent material filled with luminous phosphor gas under pressure may be located in said groove 9.

Sleeve 5 is formed integrally with a mounting pillar 12 by means of which it may be mounted in a conventional foresight protector 13 by means of a screw 14 and pin 15. The weapon may be provided with a peep-aperture form of backsight which backsight is capable of adjustment to enable zeroing of the weapon. It is not essential that a backsight be used in conjunction with the sighting device of the present invention which may, if desired, be located substantially midway between the conventional locations of the backsight and the foresight such as shown in broken line in FIGURE 1, or both the backsight and foresight may comprise sighting devices of the invention.

FIGURE 10 illustrates the use of sighting devices of the invention for both the backsight and foresight, wherein the ability of the eye to quickly and easily recognise and align concentric circles is utilised to provide accuracy and speed of aim or sighting. It can be seen from FIGURE 10, where is the outer metal sleeve, 26 is the translucent tube and 27 is the thin-walled sleeve of the backsight that an annular ring forming part of outer sleeve 5 of the foresight is presented to the firers eye between the backsight inner ring 27 and tube 26 and the foresight inner ring 7 and tube 6. The size of this annular ring is of course dependent on the distance between the backsight and the foresight and the position of the firers eye relative to the backsight.

Referring to the embodiment illustrated in FIGURE 5 the Sleeve 5 is detachably located in pillar .12 by means of post 16 engageable in slot 17 and adapted to be held at the required vertical adjustment by screw 18. The device of FIGURE 5 when used as a vertically adjustable foresight attachment does not require the more sophisticated form of adjustable backsight. It will be appreciated that the sighting device of FIGURE 5 may also be provided with means allowing transverse adjustment with respect to the mounting pillar 12 and in which case a fixed backsight may be used if desired.

For best accuracy with a deliberate shot using conventional shoulder-controlled weapons such as the type illustrated in FIGURE 1, it has been found that a ratio of length to inside diameter of tube 6 in the range 5:3.

has been very successful. However this ratio is variable to suit particular requirements in relation to weapon types and the targets to be engaged.

The ratio between the inside diameter of tube 6, i.e. the aiming circle, and the target takes into account the relationship of target movement range and practical size of engagement at various battle/sporting ranges, for example:

(a) At metres:

1) The average human head silhouette occupies /a of the aiming radius.

(2) The average human torso silhouette occupies /a of the aiming diameter.

(b) At 200 metres:

(1) The average human torso silhouette occupies /a of the aiming radius.

(2) The average figure silhouette width occupies /a of the aiming diameter.

(c) At 300 metres:

(1) The average human figure silhouette width occupies /3 of the aiming radius.

(2) The average human figure height occupies approximately Vs of the aiming diameter.

Where both the backsight and foresight comprise sighting devices as above described, the ratio of length to inside diameter of tube 6 may be varied substantially from the above described specific ratio to give a wider field of view whilst retaining the desired alignment between the line sight and the axis of the bore of the weapon by the ability of the eye to recognise two spaced-apart concentric circles whilst focusing on the target.

The particular weapon sight described in the above embodiments is effective under all lighting conditions wherein the fixing point or target can be seen by the naked eye. In bright light aim may be taken by means of the thin-walled sleeve which appears as a dark silhouette ringing the centre of the sight. The user of the weapon under these conditions after focusing upon the target adjusts his weapon until the target is located at the centre of the silhouette in the sight. He is enabled to do this by reason of the ability of the average person to locate the centre of a symmetrical pattern even though no centering aids are provided in the pattern. During aiming, the backsight aperture enables the firer to align the weapon with his line of sight, and the concentric foresight tubes act as a pair of symmetrical patterns by means of which the user is able to estimate the centre of the ring silhouette.

As lighting conditions deteriorate, the inner sleeve no longer stands out in sharp silhouette and its influence upon the aiming judgment of the user of the weapon decreases accordingly. At the same time, however, the effect of the light passing through the translucent cylinder becomes more marked and results in the appearance of an halo extending around and contrasting with the distinct view afforded by the unobstructed interior of the inner sleeve. As light conditions deteriorate yet further, so that there is no longer sufiicient light available for the user to judge the aperture purely by means of the external light, the luminous source within the foreseight produces a glow which is reflected between the exterior wall of the inner sleeve and the interior wall of the outer sleeve so as to continue to produce a clearly defined halo effect around the aperture. It is particularly important, however, that the light source within the sight should not be so bright as to have a substantial effect on the adjustment of the users eye to the prevailing light conditions, otherwise, the pupil of the aiming eye may contract to allow for the brightness of the sighting light and may not be able to react to light rays passing through the aperture from the target.

In order to achieve the greatest possible accuracy under all light conditions it is preferable, but not essential, to use a variable aperture backsight which may be adjusted as required to allow for the natural adjustment of the eye for light. It will be appreciated however that a backsight having an aperture of predetermined size may be used to cover a major range of lighting conditions without resulting in any marked effect as regards accuracy. A backsight/foresight combination of this type providing excellent accuracy through all light conditions has been described above in relation to FIGURE 10. There is a further disadvantage in having a very bright light source within the sight itself in that such a source ma give away the position of the user of the weapon with consequent danger to that person on active service.

The light-transmitting material is designed to collect the maximum light from the target and to override the luminous material until the effect of the luminous material becomes essential. The light-transmitting material is selfadjusting to light and the luminous material would not be necessary, for example, under normal moonlight conditions and would in fact destroy night vision of the fixing point or target under such conditions if the adjustment in the optical capsule tube 6 was not apparentthe same applies in daylight conditions.

The above described sight offers several advantages over sights commonly in use.

The important advantages of the sight may be listed as follows:

(a) There is provided a constant circle, regardless of light, background and target problems;

(b) It does not require the focusing sense of the eye to concern itself with this problem but permits another sense to recognize it;

(c) It permits the eye to concentrate on the fixing point or target and the point chosen as the aim to be focused;

(d) It is self-compensating for light therefore it does not offend the natural adjustment of the eye for light;

(e) By eliminating the intermediate requirements of conventional sights it is more rapid; and

(f) Its sight base for all practical purposes is the range to the target and therefore the error observed is actual, unlike conventional sights which are related to the sight base of the weapon.

The main advantage is the inherent adaptability of the sight to the lighting conditions in which it is used. As described above, the sight is effective in lighting conditions varying from a light level at which the target can barely be seen to bright daylight. In addition, the speed with which the user can aim his Weapon is greatly increased with the present sight. This is because the user does not need to focus the foresight but concentrates throughout on the target. This eliminates the delay experienced in the use of normal sights in which the user must focus the target and the foresight alternately. Further, the inner foresight sleeve has an orthoptic effect and acts as a stop in front of the users eye, thereby increasing the depth of focus of the aiming eye. It has been found in practice that a person using the sight at night can see more clearly than with the naked eye. It Will also be appreciated that the present sight is eminently suitable for aiming-off moving targets in view of the field of view provided by the sight.

The sight is particularly advantageous in military use, since it requires less training to enable a recruit to use it accurately than the sights at present used.

The above described embodiments of the invention have been given by way of example only and many variations may be made. For example, it has been found that even if the inner sleeve is dispensed with the sight is still very effective. Further, any convenient means may be employed to give the luminous ring, and this may even be dispensed with altogether if the sight is only required for use in daylight. The foresight may be used alone that is, Without a backsight, as the concentric sleeves enable the user to position his eye relative to the barrel. It is therefore to be understood that the invention is in no way limited to the specific constructional details described above.

What is claimed is:

1. A visual gun sighting device comprising an inner member of light transmitting material having an aperture in the direction of the sight line, an outer sleeve of opaque material surrounding said inner member, and an inner thin wall centering sleeve located in the aperture of said inner member.

2. A device according to claim 1 wherein said member is of tubular configuration.

3. A device according to claim 1 wherein the inner surface of the outer sleeve is highly reflective, and the inner surface of the thin-walled sleeve is non-reflective with the outer surface thereof being highly reflective.

4. A device according to claim 1 wherein a ring of luminous material is located around a surface of said inner member so as to be capable of illuminating the light-transmitting material of said member.

5. A device according to claim 1 wherein said inner member is of tubular configuration having an outer surface in part of frusto-conical form.

6. A device according to claim 4 wherein the ring of luminous material is located in a peripheral groove around the outer surface of said inner member part Waybetween the ends thereof.

7. A device according to claim 4 wherein the luminous material is a radio-activated phosphorus paint.

8. A device according to claim 4 wherein the luminous material is a phosphor gas contained under pressure in a torus of translucent material.

9. A visual gun sighting device comprising a mounting pillar member attached to an outer sleeve member having located therein a tubular member of translucent maerial, an inner thin-walled sleeve member located within said translucent tubular member and a ring of luminous material located between said outer sleeve member and said rtanslucent member, said translucent member having an outer surface in part of frusto-conical configuration.

10. A visual gun sighting device, according to claim 9, including a peep-aperture backsight mounted in alignment with said tubular member for cooperation therewith.

11. A visual gun sighting device, according to claim 9, including an identical tubular member of translucent material mounted in spaced relationship therewith and forming a foresight in cooperation with said tubular member forming a backsight.

References Cited UNITED STATES PATENTS 3,112,566 12/1963 Jones 33-47 2,969,594 l/1961 Palmer 3347 2,706,335 4/1955 Munsey 3347 1,307,646 6/1919 Watson 33--53 LEONARD FORMAN, Primary Examiner F. J. DAMBROSIO, Assistant Examiner 

